From f3d874c60ee3ada19ce26a5c4e532312b6f3a9e9 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Thu, 17 Jul 2014 18:52:42 -0700 Subject: Avoid race in single thread suspension. Don't allow more than one concurrent single thread suspension to avoid potential cycles and deadlocks where threads try to suspend each other. Bug: 16364458, 16354227 Change-Id: I907f1d5591a6aa5c241d37d6b4a34f968f98df77 --- runtime/native/java_lang_Thread.cc | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'runtime/native/java_lang_Thread.cc') diff --git a/runtime/native/java_lang_Thread.cc b/runtime/native/java_lang_Thread.cc index bae67f20e8..8f83f96318 100644 --- a/runtime/native/java_lang_Thread.cc +++ b/runtime/native/java_lang_Thread.cc @@ -116,18 +116,25 @@ static void Thread_nativeInterrupt(JNIEnv* env, jobject java_thread) { static void Thread_nativeSetName(JNIEnv* env, jobject peer, jstring java_name) { ScopedUtfChars name(env, java_name); + Thread* self; { ScopedObjectAccess soa(env); if (soa.Decode(peer) == soa.Self()->GetPeer()) { soa.Self()->SetThreadName(name.c_str()); return; } + self = soa.Self(); } // Suspend thread to avoid it from killing itself while we set its name. We don't just hold the // thread list lock to avoid this, as setting the thread name causes mutator to lock/unlock // in the DDMS send code. bool timed_out; - Thread* thread = ThreadList::SuspendThreadByPeer(peer, true, false, &timed_out); + // Take suspend thread lock to avoid races with threads trying to suspend this one. + Thread* thread; + { + MutexLock mu(self, *Locks::thread_list_suspend_thread_lock_); + thread = ThreadList::SuspendThreadByPeer(peer, true, false, &timed_out); + } if (thread != NULL) { { ScopedObjectAccess soa(env); -- cgit v1.2.3-59-g8ed1b